A 64 year old woman presents with fever, headache and a discharging right ear.
A CT scan shows appearances consistent with a large right cerebellar abscess. This is later confirmed on a MR scan. You start antibiotics to cover S. aureus, gram negatives and anaerobes and given the discharging ear, decide to send off an ENT consult.
What putative diagnosis would you put on the consult request? Acute otitis media? Chronic suppurative otitis media?
Surprising though it may seem, in a case series of 40 otogenic abscesses, acute otitis media was not implicated even once. In all but one case, the predisposing factor was a cholesteatoma.
With otogenic brain abscesses affecting the temporal lobe, spread occurs through the tegmen tympani.
For abscesses affecting the cerebellum, spread from the affected ear occurs through the Trautmann's triangle, an area bounded by the sigmoid sinus posteriorly, bony labyrinth anteriorly, superior petrosal sinus superiorly and the internal jugular vein inferiorly.
On CT, an abscess may be confused with a necrotic tumour. The best arbiter is a diffusion weighted MR scan.
In the above case, a combined neurosurgical and ENT approach would be favoured. Most experts would drain the cerebellar abscess first, followed by a radical mastoidectomy.
A CT scan shows appearances consistent with a large right cerebellar abscess. This is later confirmed on a MR scan. You start antibiotics to cover S. aureus, gram negatives and anaerobes and given the discharging ear, decide to send off an ENT consult.
What putative diagnosis would you put on the consult request? Acute otitis media? Chronic suppurative otitis media?
Surprising though it may seem, in a case series of 40 otogenic abscesses, acute otitis media was not implicated even once. In all but one case, the predisposing factor was a cholesteatoma.
With otogenic brain abscesses affecting the temporal lobe, spread occurs through the tegmen tympani.
For abscesses affecting the cerebellum, spread from the affected ear occurs through the Trautmann's triangle, an area bounded by the sigmoid sinus posteriorly, bony labyrinth anteriorly, superior petrosal sinus superiorly and the internal jugular vein inferiorly.
On CT, an abscess may be confused with a necrotic tumour. The best arbiter is a diffusion weighted MR scan.
In the above case, a combined neurosurgical and ENT approach would be favoured. Most experts would drain the cerebellar abscess first, followed by a radical mastoidectomy.
Reference
Mandalà M, Muzzi E, Trabalzini F. Giant Cerebellar Lesion in a Patient With Purulent Ear Drainage. JAMA Otolaryngol Head Neck Surg 2016. doi:10.1001/jamaoto.2016.0014
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